概述
在很app上都見過 可摺疊的頂部導航欄效果。google support v7 提供了 CollapsingToolbarLayout 可以實現這個效果。效果圖如下:
實現步驟
1.寫一個 CollapsingToolbarLayout,它有兩個 子視圖,一個就是上圖顯示的圖片(降落傘哪個)的Imageview,另一個就是 頂部導航欄toobar
2.爲 CollapsingToolbarLayout 指定屬性
app:layout_scrollFlags="scroll|exitUntilCollapsed"
3.爲ImageView 指定屬性,聲明 它是可以摺疊的
app:layout_collapseMode="parallax"
4.爲 toobar指定屬性,聲明它是固定的
app:layout_collapseMode="pin"
5.爲 CollapsingToolbarLayout 所在的父佈局(view)指定屬性,以聲明它適配當前窗體
android:fitsSystemWindows="true"
代碼
佈局xml如下
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:context="zhangyf.vir56k.app2.MainActivity">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="400dp"
android:fitsSystemWindows="true"
android:theme="@style/AppTheme.AppBarOverlay">
<android.support.design.widget.CollapsingToolbarLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
app:contentScrim="@color/colorPrimary"
app:expandedTitleMarginStart="100dp"
app:layout_scrollFlags="scroll|exitUntilCollapsed">
<ImageView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scaleType="centerCrop"
android:src="@drawable/img1"
app:layout_collapseMode="parallax" />
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:layout_collapseMode="pin"
app:popupTheme="@style/AppTheme.PopupOverlay" />
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<include layout="@layout/content_main" />
</android.support.design.widget.CoordinatorLayout>
activity代碼
其實這裏沒有什麼特別
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:context="zhangyf.vir56k.app2.MainActivity">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="400dp"
android:fitsSystemWindows="true"
android:theme="@style/AppTheme.AppBarOverlay">
<android.support.design.widget.CollapsingToolbarLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
app:contentScrim="@color/colorPrimary"
app:expandedTitleMarginStart="100dp"
app:layout_scrollFlags="scroll|exitUntilCollapsed">
<ImageView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scaleType="centerCrop"
android:src="@drawable/img1"
app:layout_collapseMode="parallax" />
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:layout_collapseMode="pin"
app:popupTheme="@style/AppTheme.PopupOverlay" />
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<include layout="@layout/content_main" />
</android.support.design.widget.CoordinatorLayout>
github演示代碼下載
https://github.com/vir56k/demo/tree/master/CollapsingtoolbarlayoutDemo